INVESTIGATIONS OF ANGIOSPERMS FROM THE EOCENE OF NORTH AMERICA: STIPULATE LEAVES OF THE RUBIACEAE INCLUDING A PROBABLE POLYPLOID POPULATION

A comparative study was made of the gross morphology, fine venation and cuticular features of Leitneria fioridana Chapman, the single living representative of the order Leitneriales and Leitneria eocenica (Berry) Brown, presumbaly a related fossil species. In addition to the type material, newly collected fossil specimens were investigated from clay pits in the Middle Eocene, Claiborne Formation, of western Tennessee and Kentucky. Foliate stipules attached to the petioles of several specimens suggest the assignment of this fossil leaf type to the genus Leitneria is incorrect. The nature of the gross morphology, fine venation and cuticular features confirms the misidentification. Previously, various specimens of this fossil leaf type have been placed in eight species of seven genera in seven families of six angiosperm orders, none of which are correct systematically. The gross morphology, venation and cuticular characters of the fossil leaf are distributed among a few extant South American genera of arborescent Rubiaceae. The fossil is an extinct rubiaceous leaf type which cannot be placed within a single modern subfamily, tribe or genus of the family. The organ genus, Paleorubiaceophyllum is proposed for these leaves. Three varieties of a single fossil species, P. eocenicum, are recognized. One variety with epidermal cells nearly twice the size of the others may represent a polyploid population.     

PTEROCARYOID FRUITS (JUGLANDACEAE) IN THE PALEOGENE OF NORTH AMERICA AND THEIR EVOLUTIONARY AND BIOGEOGRAPHIC SIGNIFICANCE

The Juglandaceae (walnut family) has an excellent fossil record of various organs extending back to the earliest Tertiary. Several genera which today are restricted to isolated geographic regions were widespread in the Northern Hemisphere during the Tertiary. This paper focuses upon the fossil record of the Pterocarya alliance of the subfamily Juglandoideae, tribe Juglandeae. The Pterocarya alliance includes only two modern genera, Pterocarya (five species) and Cyclocarya (one species), both restricted to Eurasia. Paleogene sediments of the Rocky Mountain Region have yielded three genera and four species referable to the Pterocarya alliance: Cyclocarya (two species), Pterocarya, and a new genus, Polyptera. Although three of the four Paleogene species described here are attributed to present day genera, each represents an extinct form, which cannot be accommodated by any single living species. These fossils, reviewed with other published reports, indicate that the Pterocarya alliance, like the Engelhardia alliance of the same family, was more diverse and much more widespread geographically in the Tertiary than it is today.     

A survey of species assigned to the fossil pollen genus Anacolosidites

Anacolosidites Cookson & Pike, a fossil pollen genus recorded since the Campanian, is peculiar in its morphology – six‐porate with three apertures on each hemisphere, located away from the equator, and with the distal and proximal apertures positioned over each other. Representatives of this fossil genus are widely considered to represent extant Olacaceae from tribe Anacoloseae. Olacaceae is an exclusively tropical angiosperm family with a pantropical distribution; consequently the fossils are often used to suggest a tropical climate and in addition are frequently used as a stratigraphic marker. Fossil species assigned to Anacolosidites are quite variable and may not all represent Olacaceae, in which case they may not indicate tropical climate.

The present study is a morphological survey of fossil pollen assigned to Anacolosidites; it identifies the published reports of the fossil species that probably represent positive occurrences of Olacaceae pollen in the fossil record. Within Olacaceae, Anacolosidites‐type pollen is usually compared with pollen of genera in tribe Anacoloseae, in particular: Cathedra, Anacolosa and Phanerodiscus, but never with the pollen of Ptychopetalum, a genus from tribe Olaceae with closely similar pollen to the other three genera, but with a reticulate tectum and very small circular apertures located near the equator. Nevertheless, the records of reticulate Anacolosidites species which have been excluded from the emended diagnosis are unlikely to be related to Ptychopetalum. The earliest accepted record of Anacolosidites is from the Late Cretaceous (Maastrichtian) of Germany. However, most Late Cretaceous records, and later Russian and Chinese occurrences referred to Anacolosidites, consist mainly of Normapolles‐type pollen, whereas many of the Cenozoic records assigned to Anacolosidites have a much clearer affinity with the pollen of Anacolosa, Cathedra and Phanerodiscus (tribe Anacoloseae). The newly emended genus Anacolosidites may be used as a stratigraphic marker for tropical or megathermal climatic conditions.     

Phylogenetic Systematics of Peccaries (Tayassuidae: Artiodactyla) and a Classification of South American Tayassuids

Tayassuidae is a family of pig-like Artiodactyla restricted to the New World. Despite its rich fossil history, they have received less attention from a taxonomic and phylogenetic perspective when compared to the Old World pigs, Suidae. In this study, we performed a computer assisted phylogenetic analysis using morphological and molecular data including fossil and extant Tayassuidae, using parsimony and Bayesian approaches. We recovered the monophyly of the family Tayassuidae, confirming previous proposals, as well as the monophyly of the subfamilies Hesperhyinae and Tayassuinae, and the genus Platygonus, which we placed in a new taxon of tribe level. The three living peccaries and a number of fossil species belong to a new, tribe level, monophyletic group. The genus Catagonus comes out as paraphyletic, leading us to propose to restrict the generic name to the type species, C. metropolitanus, and a new taxonomic arrangement for the remaining species previously included in it, revalidating the genera Brasiliochoerus and Parachoerus, and describing a new genus, Protherohyus, gen. nov.     

MUSOPSIS N. GEN.: A BANANA-LIKE LEAF GENUS FROM THE EARLY TERTIARY OF EASTERN NORTH GREENLAND

A fossil flora from the Late Paleocene-Early Eocene Thyra Ø Formation of eastern North Greenland (paleolatitude 77° N) has yielded monocotyledon leaf impressions with characters seen only in the closely related modem species in the families of Heliconiaceae, Musaceae, and Strelitziaceae. The combination of large costae widths and parallel, nonanastomosing, lateral veins that depart at right angles from the costae in the fossil material are features present only in leaves of extant species from these families. Three basic venation patterns also are recognized in the modem species of these families, but except for the genera Strelitzia and Phenakospermum, none of these patterns are present exclusively in any one family. Musopsis n. gen. is created for the fossil material from Greenland, but it is considered a form genus due to the lack of gross morphological features that can be used for separating leaves of the modem genera in Heliconiaceae, Musaceae, and Strelitiziaceae. It is the first known Arctic occurrence of fossil leaf material resembling this modem group of taxa.     

How diverse were ferns in the Baltic amber forest?

Diverse temperate forest types and a high atmospheric humidity have recently been suggested for the Eocene source area of Baltic amber. However, ferns are astonishingly rare as inclusions in this amber, which is in contrast to other seed‐free land plants, fungi, and lichens. Moreover, the identities of some of the few described putative fern taxa are dubious, and some fossils were even assigned to the Paleozoic seed fern genera Alethopteris, Pecopteris and to the form genus Sphenopteris containing Paleozoic and Mesozoic fern‐like leaf fossils. Here, we review previously described fern inclusions from Baltic amber and identify further fern‐like leaf inclusions as belonging to the extant angiosperm genus Comptonia (sweet ferns, Myricaceae). We conclude that only one taxon, Matonia striata (Matoniaceae), can with confidence be identified as a Polypodiopsida representative. Although “Pecopteris” humboldtiana is so far only known as sterile foliage, its leaf morphology strongly suggests that also this taxon belongs to the Polypodiopsida rather than to any other tracheophyte lineage. We propose accommodating “Pecopteris” humboldtiana in the new genus Berendtiopteris. “Alethopteris” serrata and “Sphenopteris” phyllocladoides are not to be regarded as evidence of ferns from Baltic amber. Reinvestigation of the holotypes of these two taxa did not reveal to which tracheophyte lineages these fossils belong. We suggest that the scarcity of fern remains from Baltic amber may reflect both a relatively low fern diversity in the source area of the fossil resin, and an absence or rarity of epiphytic and climbing ferns as observed in modern temperate forest ecosystems.     

FRUITS AND SEEDS OF TRIBE GORDONIEAE (THEACEAE) FROM THE EOCENE OF NORTH AMERICA

A new genus and species Gordoniopsis polysperma and two new species of Gordonia (Gordonieae, Camellioideae, Theaceae) are described based on fossil fruit and seed remains. These specimens are part of a large flora consisting of various plant organs from the middle Eocene Claiborne Formation in western Kentucky and Tennessee. Gordoniopsis is a five-valved loculicidally dehiscent capsule similar to capsules of Gordonia but differing in having unwinged seeds and a greater number of seeds per locule. The two Gordonia species are among the earliest unequivocal records of the genus and two of only four fossil Gordonia species known with in situ seeds. Two extinct genera, Gordoniopsis and Andrewsiocarpon, and the extant genus Gordonia in the tribe Gordonieae are known from the middle Eocene Claiborne flora, suggesting an early radiation within the tribe. Based on a survey of Recent fruits and seeds we concur with Keng's proposal to merge Laplacea with Gordonia.     

On the reclassification of species assigned to Candida and other anamorphic ascomycetous yeast genera based on phylogenetic circumscription

Multigene phylogenies have been instrumental in revising the classification of ascosporic (teleomorph) yeasts in a natural system based on lines of descent. Although many taxonomic changes have already been implemented for teleomorph taxa, this is not yet the case for the large genus Candida and smaller anascosporic (anamorph) genera. In view of the recently introduced requirement that a fungal species or higher taxon be assigned only a single valid name under the new International Code of Nomenclature for algae, fungi, and plants (Melbourne Code), the current species of Candida and other anamorph yeast genera must undergo revision to make genus membership consistent with phylogenetic affinities. A review of existing data and analyses shows that certain Candida species may be assigned to teleomorph genera with high confidence using multigene phylogenies. Candida species that form well-circumscribed phylogenetic clades without any teleomorph member justify the creation of new genera. However, a considerable number of Candida species sit at the end of isolated and often long branches, and hence cannot be assigned to larger species groups. They should be maintained in Candida sensu lato until studied by multigene analyses in datasets with comprehensive taxon sampling. The principle of name stability has to be honoured to the largest extent compatible with a natural classification of Candida species.     

COMPARATIVE PALEOBIOCHEMISTRY OF SOME FOSSIL AND EXTANT FAGACEAE

A Fagus-like leaf fossil (cuticular compression) with an attached fruit, differing from any known Fagus species (fossil or extant) or other fagoid taxa, has been discovered from the Miocene Clarkia Lake deposits of northern Idaho. Because of its unusual morphology (especially the fruit) the fossil taxon has been described as a new genus and species, Pseudofagus idahoensis Smiley and Huggins. The successful previous use of paleobiochemistry in studies of fossil taxa from the Miocene Succor Creek Flora of Oregon suggested that chemical data might help clarify the taxonomic affinities of Pseudofagus. Indeed, examination of the chemistry of the fossil, Pseudofagus idahoensis, and comparison with extant Fagus species and related fagoid genera indicate that: 1) based on steroid chemistry, Pseudofagus idahonesis does belong in the Fagaceae; 2) like all extant species of Fagus, the fossil lacks the tannin component, ellagic acid, which separates it from other extant fagoid genera, and 3) its simple flavonoid pigment profile places it closest to the extant North American Fagus grandifolia or the European/Eurasian Fagus sylvatica. However, the exclusive presence of an isorhamnetin (3'-methoxyquercetin) 3-0-glycoside, onocerane, and 5α-cholestane imparts a species-specific chemical character to Pseudofagus idahoensis, which also sets it apart from extant species of Fagus. While the chemistry does not decide the taxonomic level to be accorded to the fossil, it certainly supports, along with morphology and anatomy, the distinctness of Pseudofagus and its proposed relationships within the Fagaceae.     

A new terrestrial amphipod from tertiary amber deposits of Chiapas province,Southern Mexico

Transitroides morsei new genus, new species, is described from late Oligocene Early Miocene amber deposits of Chiapas Province from southern Mexico. This new taxon is the first known fossil member of the amphipod family Talitridae and superfamily Talitroidea. It appears intermediate between regional extant palustral (salt‐marsh) genera and fully terrestrial landhoppers of the genus Caribitroides. These beetle‐like crustaceans form a significant part of the forest‐floor leaf‐litter communities in some tropical parts of the globe. Extant terrestrial amphipods occur in south‐central Mexico and adjacent rain forest habitats in Central America and the Caribbean. Their occasional use of arboreal habitats in search for decaying organic matter, which serves as food, explains their occurrence in fossilized resin.     

A NEW LOOK AT AN ANCIENT ORDER: GENERIC REVISION OF THE BANGIALES (RHODOPHYTA)1

The red algal order Bangiales has been revised as a result of detailed regional studies and the development of expert local knowledge of Bangiales floras, followed by collaborative global analyses based on wide taxon sampling and molecular analyses. Combined analyses of the nuclear SSU rRNA gene and the plastid RUBISCO LSU (rbcL) gene for 157 Bangiales taxa have been conducted. Fifteen genera of Bangiales, seven filamentous and eight foliose, are recognized. This classification includes five newly described and two resurrected genera. This revision constitutes a major change in understanding relationships and evolution in this order. The genus Porphyra is now restricted to five described species and a number of undescribed species. Other foliose taxa previously placed in Porphyra are now recognized to belong to the genera Boreophyllum gen. nov., Clymene gen. nov., Fuscifolium gen. nov., Lysithea gen. nov., Miuraea gen. nov., Pyropia, and Wildemania. Four of the seven filamentous genera recognized in our analyses already have generic names (Bangia, Dione, Minerva, and Pseudobangia), and are all currently monotypic. The unnamed filamentous genera are clearly composed of multiple species, and few of these species have names. Further research is required: the genus to which the marine taxon Bangia fuscopurpurea belongs is not known, and there are also a large number of species previously described as Porphyra for which nuclear SSU ribosomal RNA (nrSSU) or rbcL sequence data should be obtained so that they can be assigned to the appropriate genus.     

Cladistic analysis of morphological characters in the eulophine tribe Cirrospilini (Hymenoptera: Eulophidae)

A total of 56 morphological characters were analyzed for 53 cirrospiline species that represent all of the 17 described genera of the tribe. The other taxa of the Eulophinae included in the analysis were six species of six representative genera in the tribe Eulophini, a species of Elasmus (the only genus comprising the tribe Elasmini), and a species of Trichospilus (unplaced). Trichospilus and two of the six genera of Eulophini examined were placed within Cirrospilini. Monophyly of Cirrospilini (when these two genera of Eulophini and Trichospilus are included) and of the cirrospiline genera for which more than one species were examined was supported, but the relationships between the genera were poorly resolved. An exception was Cirrospilus, the largest genus in the Cirrospilini, monophyly of which was not supported to any extent.     

Phylogeny of the North American catfish family Ictaluridae (Teleostei: Siluriformes) combining morphology,genes and fossils

We performed the first combined‐data phylogenetic analysis of ictalurids including most living and fossil species. We sampled 56 extant species and 16 fossil species representing outgroups, the seven living genera, and the extinct genus ?Astephus long thought to be an ictalurid. In total, 209 morphological characters were curated and illustrated in MorphoBank from published and original work, and standardized using reductive coding. Molecular sequences harvested from GenBank for one nuclear and four mitochondrial genes were combined with the morphological data for total evidence analysis. Parsimony analysis recovers a crown clade Ictaluridae composed of seven living genera and numerous extinct species. The oldest ictalurid fossils are the Late Eocene members of Ameiurus and Ictalurus. The fossil clade ?Astephus placed outside of Ictaluridae and not as its sister taxon. Previous morphological phylogenetic studies of Ictaluridae hypothesized convergent evolution of troglobitic features among the subterranean species. In contrast, we found morphological evidence to support a single clade of the four troglobitic species, the sister taxon of all ictalurids. This result holds whether fossils are included or not. Some previously published clock‐based age estimates closely approximate our minimum ages of clades.     

Bennettitalean leaf cuticle fragments (here Anomozamites and Pterophyllum) can be used interchangeably in stomatal frequency‐based palaeo‐CO2 reconstructions

Abstract: Bennettites are an abundant and frequently well‐preserved component of many Mesozoic fossil floras, often playing an important ecological role in flood plain vegetation communities. During a recent study focusing on stomatal indices of Triassic–Jurassic fossil plants, it became evident that the leaf fragments of two bennettite genera Anomozamites Schimper (1870) emend. Harris (1969) and Pterophyllum Brongniart (1825) display a significant overlap of leaf shape as well as cuticular characters. Owing to the preference of recognition of single taxa (ideally species) for the stomatal method, we use a database of 70 leaf fragments of Anomozamites and Pterophyllum compressions from five isotaphonomic Late Triassic sedimentary beds of Astartekløft in East Greenland to test whether leaf and cuticle fragments of the two genera can be separated using a range of quantitative and qualitative morphological and statistical analyses. None of the observed characters – including stomatal frequencies – could be applied to separate the fragments of the two genera into well‐defined groups. Our results therefore indicate that fragmented material and dispersed cuticles cannot be utilized to distinguish between Anomozamites or Pterophyllum at the genus level, but that instead these cuticle fragments may be used interchangeably as stomatal proxies. Classification of fossil leaves into either of these genera is thus only possible given adequate preservation of macro‐morphology and is not possible based solely on cuticle morphology. We suggest that this large inter‐ and intra‐generic morphological variation in both leaf and cuticle traits within Anomozamites and Pterophyllum may be related to the bennettites’ role as understory plants, experiencing a range of micro‐environmental conditions, perhaps depending mainly on sun exposure. Based on the results obtained in this study, we conclude that Anomozamites and Pterophyllum cuticle fragments can be employed interchangeably in palaeo [CO₂] reconstructions based on the stomatal method, thus potentially annexing a plethora of bennettitalean fossil plant material as CO₂ proxies, including dispersed cuticles.     

The tribeSmyrnieae (Umbelliferae) in the light of serotaxonomical analysis

An immunochemical investigation of some Old-WorldUmbelliferae belonging to the tribeSmyrnieae in current classifications has clearly demonstrated that the genera of this tribe do not form a natural monophyletic taxon. The presence of a more or less deep groove on the commissural side of the seeds cannot be regarded as an essential marker of phylogenetic relationships within this family.     

ANATOMICALLY PRESERVED SEED CONES OF THE PINACEAE FROM THE EARLY CRETACEOUS OF VIRGINIA

A collection of anatomically preserved conifer cones from the Early Cretaceous of Virginia contains two new species of the extinct pinaceous genus Pityostrobus. Superficially, the fossil cones resemble those of modern species of Picea. However, the fossils reveal such a peculiar mixture of anatomical features that they cannot be assigned to any extant genus of the Pinaceae. One of the new species, Pityostrobus hueberi, is most comparable with Pityostrobus corneti Alvin from the Early Cretaceous of Belgium. Pityostrobus virginiana, the other new species, differs from all other members of the genus in only slight—but nonetheless significant—attributes. Pityostrobus hueberi and P. virginiana are the first species of this genus to be reported from Early Cretaceous sediments of the North American Atlantic Coastal Plain. As such, they increase our knowledge of the structural variation exhibited by ancient members of the Pinaceae.     

Using molecules and morphology to infer the phylogenetic relationships and evolutionary history of the Dirini (Nymphalidae: Satyrinae), a tribe of butterflies endemic to Southern Africa

The first empirically supported phylogenetic hypothesis of relationships for the southern African endemic butterfly tribe Dirini is presented. Data derived from the morphology and ecology of the adults and immature stages (33 characters), and portions of the mitochondrial gene cytochrome oxidase I (COI) and the nuclear genes elongation factor 1α (EF1α) and wingless (WG) (totalling 1734 bp) were used to infer the relationships of the in‐group genera. An expanded molecular dataset using four genera from the Nymphalini and Satyrini to root the tree, and three genera from the Melanitini to test the monophyly of the tribe, was analysed using parsimony and Bayesian methods. Estimates of divergence times were calculated using two fossil calibrations under a relaxed molecular clock model. The monophyly of the tribe and each in‐group genus were strongly supported. Key findings are the sister‐taxon relationship of Aeropetes and Tarsocera, the apparent simultaneous or nearly simultaneous radiation of four lineages, the polyphyly of the species within Torynesis, and the apparent trans‐Atlantic dispersal of the ancestors of Manataria about 40 Ma. Estimates of divergence times indicate that the tribe has undergone two major radiations since its origin: the first when they left forest habitats in the mid–late Oligocene, shortly after the radiation of the grasses (Poaceae), and the second in the early‐middle Pliocene, coinciding with the aridification of southern Africa and the spread of conditions that favoured C₄ grasses over the C₃ grasses that dirine larvae prefer to eat. The high species diversity within the tribe appears to be partly a taxonomic artefact that may have resulted from the misinterpretation of climate‐related phenotypic variation within extant species. Relocation and breeding experiments should test this hypothesis.     

PALAEOSTACHYA DIRCEI N. SP., AN AUTHIGENICALLY CEMENTED EQUISETALEAN STROBILUS FROM THE MIDDLE PENNSYLVANIAN OF SOUTHERN ILLINOIS

Equisetalean strobili normally are encountered as disarticulated organs. This condition has necessitated the creation of 12 form genera to accommodate the various morphological architectures and anatomical configurations. Taxonomically useful characteristics, which are discernable in permineralized specimens, are rarely distinguishable in coalified compressions due to their destruction during diagenesis and coalification. Therefore, genera established on the position of sporangiophore-trace origin, such as Schimperia Remy and Remy, are untenable when dealing with coalified compressions. Although the two largest genera of strobili, Calamostachys Schimper and Palaeostachya Weiss, may be synonymous, it is proposed that these form genera be retained when dealing with coalified compression specimens. Each genus provides a particular architectural concept for specimens which may not be assignable to the species level. Calamostachys and Palaeostachya are highly overspeciated genera. It is suggested that characteristics necessary to delimit new species include bract height, degree of bract fusion, disposition of bracts, bract: sporangiophore ratio, number of sporangia per sporangiophore, and sexual status.